We're going to head to wimbledon, where there has been plenty of excitement. There's been big upsets. Young upstarts. And Serena Williams' mystery health scare. Lara is in the middle of the action. Good morning to you. Good morning to you, Amy and David, from the broadcast roof. It's a beautiful day at wimbledon. And what a stunning road to the semifinals, which begin today, as so many of the giants in this sport were upset by what Chris evert calls the next wave. I think Andy Murray may have said it best after his defeat. For him and so many, it was just a really bad day at the office. One year after making history, defending champ Andy Murray was defeated Wednesday, ending his hopes for a second wimbledon tight. Wow. Nadal and Murray out. Reporter: The duke and duchess stunned as the hometown hero went down in straight sets to Gregor Dimitrov. Dimitrov, maria sharapova's boyfriend, is one of several up-and-comers, taking aim at the old guard. Hello to this superstar in the making. We want to prove to the big guys that, you know, we're around the corner. Reporter: And Murray is just the latest top player to fall victim to this new legion. On Tuesday, two-time wimbledon champ Rafael Nadal was stunned by nick kyrgios, whose ranking is 144th in the world. Two familiar names did manage to survive this youthquake. Seven-time champ roger Federer and Novak djokovic won their quarterfinal matches, setting up semifinal showdowns with two fresh-faced foes. She is not well. Reporter: Meanwhile, a day after Serena Williams withdrew, looking shaky on the court, posted this photo on instagram. Many are wondering why Williams was allowed to play at all. It was clear, the moment she set foot on the court, something was wrong. And why it went on for a couple games, I don't know. Reporter: We are awaiting word from Serena's agent on how she is doing today. I want to introduce you to one of the biggest characters at wimbledon. This is Rufus, the 6-year-old hawk which is something of a movie star, if you will. I know he's treated like a movie star because he has his own commercial for Stella beer. His own website. His own Twitter handle, Rufus the hawk. His control is avian control here. And it is crucial here at the all England club. It's important to keep the pigeons away during match time. He comes every morning, sweeps through. Exactly. And it's very important today, as we begin the semifinals.

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